0

Full Content is available to subscribers

Subscribe/Learn More  >

Accounting for Eccentricity in Compressor Performance Predictions

[+] Author Affiliations
Anna M. Young, Teng Cao, Ivor J. Day, John P. Longley

University of Cambridge, Cambridge, UK

Paper No. GT2016-56681, pp. V02AT37A017; 11 pages
doi:10.1115/GT2016-56681
From:
  • ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition
  • Volume 2A: Turbomachinery
  • Seoul, South Korea, June 13–17, 2016
  • Conference Sponsors: International Gas Turbine Institute
  • ISBN: 978-0-7918-4969-9
  • Copyright © 2016 by ASME

abstract

It is known that the tip-clearance gap plays a pivotal role in determining the performance of an aero-engine compressor, both in terms of stability and pressure rise. However, the exact effect of tip-clearance size on stall margin over the range of clearances experienced during engine operation is not known, and most designers substitute rules of thumb for real knowledge when developing new compressors.

Eccentricity in the tip-clearance is also known to affect compressor performance, though again little work has been done to quantify the penalties. It is generally assumed that the stall margin of an eccentric machine will be approximately equal to that of a concentric machine with a clearance equal to the maximum eccentric clearance. Results given in this paper show a stabilising effect of the small tip-clearance sector of an eccentric compressor on the large tip-clearance sector, so the penalty on stall margin is not as large as commonly assumed. It is shown that the stall margin penalty in a single-stage eccentric machine is only 50–60% of that which a concentric compressor with clearance equal to the maximum clearance would exhibit. In addition, the effect of eccentricity is shown to diminish as the average clearance is increased.

In this paper, experiments and computational modelling are used to examine the effects of eccentric tip-clearance on flowfield redistribution and compressor performance. In particular, the three-dimensional nature of the flowfield generated by an eccentric gap is shown for the first time. The purpose of this work is not to provide ‘hard-and-fast’ design rules for eccentric compressors (this cannot be done on the basis of single-stage measurements), but to provide a starting point for a better physical understanding of the problem.

Copyright © 2016 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In